Nisekoi
Yeah, I definitely like this, since the harem, and the childhood memories, and the 'dere-deres' are so kawaii. Just makes you wanna kill this Raku Ichijou the main character, so dense, playing so hard to get, yet nice to others.
Story:
Raku Ichijo the heir of a Yakuza got engaged to the daughter of a mafia gang, Chitoge Kirisaki. Even when he has someone he likes, he's still nice to her. So much 'dere', so much fun.

